[Forever]

Originally Posted by CycloneGU

This is what I suggested as well for a possible format. Thinking further, this would register it in the Pokédex but not show it as owned (leaving you to import one for ownership purposes), meaning you can reveal the entire Pokédex through expanding new exhibits over the course of the story or in the post-game.

Cyclone

That'd be an awesome feature for zoos to have. Actually maybe it could be something post-game, in regards to the pokedex entries, otherwise we just see Pokemon out on display. Because really, finding over 700 Pokemon post-game isn't the easiest task.